Clashnessie beach: Creatures and a Seaweed Puzzle
The Field Club’s early summer survey for the Community-led Marine Biodiversity Monitoring project took place on 16 May 2022. As the weather was kind, we were able to make a much closer inspection of the lower boulder beds, which showed up much of interest. A detailed list of finds can be found here; the main points are outlined in the following notes.
Anemones and Worms
Anemones, both beadlet (photo 1) and dahlia, were numerous in the rock pools at the foot of the cliff right through to the boulder beds in the lower shore. Dahlia anemones are particularly interesting, as they like to try to camouflage themselves with small pieces of sand and shell (photo 2). Evidence of neroid and sand mason worms was found in the boulder bed, along with a green leaf worm (photo 3).
Crustaceans
The lower boulder bed revealed several crabs, notably the long-clawed porcelain crab (photo 4), as well as shore (photo 5) and edible crabs. All were juveniles. A common starfish also made an appearance (photo 6).
The boulder bed yielded breadcrumb sponge, the different crumb-of-bread sponge (photo 7) and a sea squirt.
Molluscs
We found numerous examples, mostly common limpet and various periwinkles (photo 8). The most striking was a blue-rayed limpet found on Tangle (photo 9). Fresh barnacle spat (photo 10) occurred in rock pools and on exposed rocks lower down the beach.
A Seaweed Puzzle
The beach has a huge variety of seaweeds of all colours (photo 11), shapes and sizes. We found bunny ears, sea lettuce and twisted siphon weed, amongst others (see the detailed list for comprehensive notes). Interestingly, there is a narrow zone of green algae which extends seawards between the boulder bed and sandy shore (photo 12). This comprises mainly sea lettuce and gut weed. As yet, we have been unable to identify the reason for this – there is no freshwater outlet – but a similar phenomenon is to be found at other Assynt beaches.
The next survey will be in the early autumn.
Charlie Leeson